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11.
This article uses a smooth transition regression (STR) model to research the income elasticity of the health care expenditure of China’s urban residents in the 1990–2013 period. The results demonstrate that if the real income of China’s urban residents that lags a period is taken as a transition variable, urban residents’ health expenditure follows an LSTR1 nonlinear two-regime model. Here, the income elasticity of health care expenditure of China’s urban residents is 1.4919 in 1990–2002 and 1.2216 in 2003–2013. Overall, the income elasticity of health care of China’s urban residents is greater than 1, indicating that health care is a luxury.  相似文献   
12.
Mobile communication failure can occur when mobile traffic exceeds the manageable level. This depends on frequency bandwidth. Mobile communication failure causes inconveniences in a user's daily life that lead to social and economic damage. To address this issue, mobile telecommunications companies deploy additional bandwidths and develop new technologies, but these are costly strategies. This study applies a spike model based on a contingent valuation method (CVM) to measure the inconvenience cost resulting from mobile communication failure. The mean monthly willingness-to-pay (WTP) to avoid communication failure per user is estimated to be KRW 898.14 (USD 0.80) over a period of five years in our study. The inconvenience cost borne by the population is estimated to be KRW 2.97 trillion (USD 2.61 billion). Users experiencing greater frequency of communication failure are found to be willing to pay more to avoid the inconvenience. When excluding respondents citing zero-WTP, the mean WTP per user was calculated to be KRW 3426.41 (USD 3.01). Data traffic usage and frequency at which communication failure is experienced are variables that exhibit statistically significant effects on WTP to avoid mobile communication failure. Overall, estimation results show that a price discrimination based on data traffic usage or quality can be considered by mobile telecommunications companies and regulators to address the issue of data traffic inducing mobile communication failure.  相似文献   
13.
徐明杰  韩印 《物流科技》2020,(1):106-110
为了合理地优化交叉口信号配时,通过分析交叉口的评价指标,建立了以车辆的平均延误、停车次数最小、交叉口整体通行能力最大、各相位有效绿灯时间和交叉口周期时长作为约束条件的数学模型。并通过改进前人研究基础上的动态加权系数,将多目标的非线性优化问题转化为单一目标的非线性规划问题,为了得出更科学稳定的解,提出了改善粒子群算法系统稳定性的2种方法,并将其与粒子群算法结合起来。然后以Matlab为求解工具,结合临邑市某一交叉口实例进行求解分析。最后的结果表明,在使用改进后的粒子群算法进行优化后交叉口通行能力较之现状提升了9%,延误下降了28%,停车次数下降了9%,且各项优化结果均优于Webster,改进后的算法在程序中运行300代,到216代才开始收敛,而未改进的算法稳定性较差,优化结果和收敛曲线则随着实验次数的变化而变化,最后的结论证明了该算法和模型的可靠性。  相似文献   
14.
ABSTRACT

The conventional monetary policy rule describes a simple linear relationship between the domestic interest rate, inflation rate and output gap. An important extension to this rule is to incorporate the forward-looking behaviour of central banks, where it is assumed that they target an expected level of inflation instead of its current realised value. Using quarterly observations for the period 1993:1-2018:2, this paper investigates whether the conduct of monetary policy in Australia can be described by a forward-looking linear monetary policy rule, or by a nonlinear forward-looking monetary policy rule. In particular, the nonlinear forward-looking monetary policy rule is analysed in a regime-switching framework using a smooth logistic transition regression model. While the results show that the conventional forward-looking linear monetary policy rule describes the application of monetary policy in Australia reasonably well, the interest rate setting behaviour of the RBA is best described by a nonlinear forward-looking monetary policy rule.  相似文献   
15.
ABSTRACT

A panel smooth transition regression model was adopted to analyse the non-linear impact of oil prices on oil demand. Data for 42 countries was obtained from the International Energy Agency for the time period spanning from January 1990 to June 2017. The results indicate that a threshold value does exist. Furthermore, when the oil price was lower than this threshold value, a positive relationship between oil price and oil demand was observed. When the price of oil was higher than the threshold value, however, a negative relationship between price and demand was found.  相似文献   
16.
Previous studies have investigated asymmetries in the effects of monetary policy on the real economic activity by using either vector autoregressive (VAR)-based regime-switching models with smooth transition technique or Gaussian functions to parameterise the dynamic effects of structural shocks on the economy. These kinds of VAR models assume asymmetry as a short-run relationship between the series since the long-run neutrality hypothesis of money states that monetary policy can only affect productive capacity of the economy in the short run, but not in the long run. The recent theoretical literature shows that this hypothesis is not quite right. Thus, this paper examines the extent to which monetary policy has a long-run asymmetric effect on output in a number of Organisation for Economic Co-operation and Development countries by using a nonlinear hidden cointegration analysis within a likelihood-based panel framework. The findings indicate that there is a long-run relationship between the real interest rate as an indicator of monetary policy and the growth rate of real output in five countries out of nine under review. This gives support for the view that output has responded asymmetrically to the real interest rate changes. The economic implication of our results is that monetary policy affects positive and negative output fluctuations differently.  相似文献   
17.
18.
We analysed a county‐level data set of single‐season rice yield and daily weather outcomes in China to examine the effects of temperature on China's rice sector. We found that rice yield exhibited highly nonlinear responses to temperature changes: rice yield increased with temperature up to 28°C and decreased sharply with higher temperatures. Holding current growing seasons and regions constant, average rice yield in China is projected to decrease by 10–19 per cent by 2050 and 11–33 per cent by 2070 due to future warming under the global climate models HadGEM2‐ES and NorESM1‐M. These results imply that future warming poses a major challenge for Chinese rice farmers and that the effectiveness of adaptations will depend on how well they reduce the negative temperature impacts on rice yield because of very hot days.  相似文献   
19.
在雷达目标跟踪中,系统量测信息通常在球坐标系下获得。为了采用经典卡尔曼滤波算法实现有效目标跟踪,通常采用量测转换方法将非线性量测信息转换到直角坐标系中。针对传统量测转换方法基于量测值计算转换误差统计特性而导致的估计结果有偏问题,提出了一种基于预测值的量测转换方法,并将其与卡尔曼滤波算法相结合,获得了一种基于预测值量测转换的卡尔曼滤波跟踪算法。仿真结果表明,与现有的基于量测转换的卡尔曼滤波算法相比,该算法能在不提高运算量的情况下有效改善目标跟踪效果,跟踪精度提升约20%。  相似文献   
20.
In light of the growing national priority to develop and revitalise entrepreneurship in emerging economies, our understanding of barriers to serial entrepreneurship (SE) in such a context warrants further scholarly attention. Using insights from Ghana, an integrated framework of endogenous and exogenous barriers to SE is advanced. The study identified factors such as stigmatisation of business failure, fear of failure, successive governments’ suspicion of the private sector and lack of a clear national policy as barriers to the development of SE. By creating conditions for de-stigmatising of failure, countries would be able to create conditions for more serial entrepreneurs to emerge and flourish. The analysis also indicates that reinvigorating entrepreneurship by providing space and opportunity for failed entrepreneurs to re-emerge would enable such countries to enhance entrepreneurial activities and improve economic development. The implications for technology analysis and strategic entrepreneurship literature are identified and examined.  相似文献   
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